APOD.pl: astronomiczne zdjęcie dnia

Codziennie nowy obraz lub zdjęcie naszego fascynującego Wszechświata
wraz z krótkim objaśnieniem napisanym przez zawodowego astronoma.
Zobacz więcej!

13 lipca 1998

GRB 980703: A Reassuring Redshift
Źródło: S. G. Djorgovski, S. R. Kulkarni, (Caltech) et al., Keck Observatory

Opis: In the old days, just over a year ago, astronomers had little idea of the true distance to gamma-ray bursts. Did these enigmatic explosions occur in our outer Galaxy, or in the outer Universe? Last May, a first telling distance measure was made - GRB 970508 showed an absorption line with a redshift of about 0.8 - indicating that this gamma-ray burst (GRB) was an enormous distance away. Skeptics, however, are not always convinced by an unrepeated measurement. Since then, though, other tantalizing coincidences have occurred: GRB 971214 occurred unusually near a galaxy with the enormous redshift of 3.4, and GRB 980425 occurred unusually near a peculiar low-redshift supernova. Skeptics were intrigued. Now, the potentially definitive implications of the above-pictured optical transient might impress even the cautious. GRB 980703's optical transient shows a well-measured redshift from both an absorption line and an emission line: 0.97. The above negative highlights the uncommon transient source with the label "OT", while letters designate common comparison stars.

Jutro: At Work on Mars


< | Archiwum | Lista tematyczna | Szukaj | Kalendarz | Słownik | Edukacja | O APOD | >

Autorzy i wydawcy: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.